An AwesomeBad Idea: The Atomic Dreadnought

[asnys]

So, I know this is a bad idea; I'm only posting this to exorcise it from my brain.

Time frame: late '40s/early '50s, before guided anti-ship missiles were common. Start with a battleship. We want this thing to be heavily-armored enough to resist near-misses from a nuclear weapon, direct hits from light conventional weapons, and resistant to radiation; not sure we can get that with the materials of the time, but let's not let that stop us. We give it a nuclear power plant, of course. For both offensive and defensive armament, we fit it with nuclear artillery - long-range guns for offensive weapons, and short-range "atomic flak" guns for defensive. So if it sees an air raid incoming, it detonates some atomics in the general direction of the incoming, relying on its armor to protect it from the blast and radiation. And of course, it has nuclear depth charges for protection from submarines. The basic idea is to make the environment around it into an atomic inferno so hellish that only something as armored as it can survive.

Obviously, there's only a very short time period in which this monster is even conceivable as a viable idea, before anti-ship missiles get accurate and heavy enough to sink it from range. In fact, if you started building it in 1950, it would probably be obsolete by the time it clears the slipway. And arming it would require a significant percentage of the entire US nuclear arsenal of the time. But it's such an atompunk idea I can't get it out of my head, so I'm inflicting it on all of you. Specifically, I'd like to discuss:

• Is this even a theoretically feasible design - could they make armor that good in that time frame?
• What sort of specifics can we put on the design - armor thickness, shell types, etc.?
• When, specifically, does it become too vulnerable to air attack to be even discuss-able?

If the mods feel it necessary to move this to ASB, I understand, but I would like to point out that there is nothing about this design that is actually impossible, it's just a very, very bad idea.

 

[Vikingstar]

I can't remember which BB was at the 1946 bomb tests at Bikini Atoll, but the armor of the turrets stopped about 90% of the radiation released by the bomb--it wasn't enough. Within a day anybody on board would be dead from radiation poisoning. So, it would be unworkable to design a "dreadnought" that could withstand close hits and still have the crew survive.

Unless, of course, you want to ASB this to the Fallout universe...then it's a awesomebad great idea.

 

[asnys]

I can't remember which BB was at the 1946 bomb tests at Bikini Atoll, but the armor of the turrets stopped about 90% of the radiation released by the bomb--it wasn't enough. Within a day anybody on board would be dead from radiation poisoning. So, it would be unworkable to design a "dreadnought" that could withstand close hits and still have the crew survive.

Unless, of course, you want to ASB this to the Fallout universe...then it's a awesomebad great idea.

It depends on how close a detonation you need to be able to survive, and how optimized your armor is for resisting radiation. The gamma tenthing thickness for steel is about 3.3 inches, and a 10 kT device puts out 500 REM at a radius of 1.25 km, so 6.6 inches of steel - or 3.3 inches of steel and a bit more then an inch of lead - will cut that to 5 REM - not good for you, but not going to produce acute effects.

 

[RamscoopRaider]

Define near miss Nagato, laid down 1917, survived within 1000 yards of a 23 kt airburst with light damage. Of course she was stern on. She took 5 days to sink from a 23 kt submerged detonation 870 yards away, damage control may have saved her

I would guess to get maximum range, for the US Main Armament would be the 18"/47, either three or four triples, with a nuclear, likely ~25 kt, 4000lb AP shell and some sort of HE. secondary would be the 8"55 Mark 16, in some sort of custom single mount, as the Triple would traverse too slow and a theoretical twin is likely the same, probably with high elevation, and a 335lb AP and 260 lb HE shell, plus a modified W33 type shell. Lighter fare would be the 3"/70 in twin mounts with conventional shells. No nuclear depth charges, too dangerous for the Battleship, too likely to break your own keel(note nuclear depth charges were only ever air deployed), instead revert to the old method of carrying torpedoes and load say 8 21" tubes with Mark 45 Torpedoes, or just mount ASROCs somewhere

Armor would probably just be Montana's scheme modified with lead shielding mounted on a 1.25" STS plate a deck before, plus extra scrubbers and radiation shielding where needed. Maybe have a quadruple bottom for resistance to underwater bursts

Too vulnerable in 1955 when the KS-1 Komet enters service, or a year or two later when enough get built, has a heavy enough warhead to be nuclear, and can launch out of nuclear Flak range

 

[asnys]

Define near miss Nagato, laid down 1917, survived within 1000 yards of a 23 kt airburst with light damage. Of course she was stern on. She took 5 days to sink from a 23 kt submerged detonation 870 yards away, damage control may have saved her

"As close as we can get away with", basically. Which will depend a lot on the yield. I'm figuring tens of kilotons, though, not megatons.

I would guess to get maximum range, for the US Main Armament would be the 18"/47, either three or four triples, with a nuclear, likely ~25 kt, 4000lb AP shell and some sort of HE. secondary would be the 8"55 Mark 16, in some sort of custom single mount, as the Triple would traverse too slow and a theoretical twin is likely the same, probably with high elevation, and a 335lb AP and 260 lb HE shell, plus a modified W33 type shell. Lighter fare would be the 3"/70 in twin mounts with conventional shells.

Carrying some conventional munitions makes sense - not everything is worth a nuke - but would it make sense to carry any conventional-only guns, or only guns able to fire a nuclear payload?

Armor would probably just be Montana's scheme modified with lead shielding mounted on a 1.25" STS plate a deck before, plus extra scrubbers and radiation shielding where needed. Maybe have a quadruple bottom for resistance to underwater bursts

I'm imagining a situation where you have your standard heavy battleship armor, plus "safe boxes" with additional lead radiation shielding. When under combat conditions, everyone gets inside a safe box.

Too vulnerable in 1955 when the KS-1 Komet enters service, or a year or two later when enough get built, has a heavy enough warhead to be nuclear, and can launch out of nuclear Flak range

This may be a stupid question, but would the Komet be vulnerable to atomic flak? From the wiki page, it looks like a drone made out of a Mig, so I'm wondering if they could just shoot it down.

 

[Riain]

Only semi-relevent but I once read that HMS Rodney and Nelson were capable of being zipped up against chemical attack. Were other post WW1 warships designed this way and would it help with nuclear fallout?

 

[asnys]

Only semi-relevent but I once read that HMS Rodney and Nelson were capable of being zipped up against chemical attack. Were other post WW1 warships designed this way and would it help with nuclear fallout?

I don't know about WW1/2-era ships, but I believe most Cold War-era ships were designed to button up against fallout, and fitted with water sprayers to wash fallout off the superstructure.

 

[RamscoopRaider]

"As close as we can get away with", basically. Which will depend a lot on the yield. I'm figuring tens of kilotons, though, not megatons.



Carrying some conventional munitions makes sense - not everything is worth a nuke - but would it make sense to carry any conventional-only guns, or only guns able to fire a nuclear payload?



I'm imagining a situation where you have your standard heavy battleship armor, plus "safe boxes" with additional lead radiation shielding. When under combat conditions, everyone gets inside a safe box.



This may be a stupid question, but would the Komet be vulnerable to atomic flak? From the wiki page, it looks like a drone made out of a Mig, so I'm wondering if they could just shoot it down.

400 yards is probably doable, a sub survived that without sinking at Crossroads with a 23 kiloton device. Of course it depends on the orientation, hitting bow or stern on would hurt less than broadside, so you are going to want a very stable ship

Some conventional guns, mainly for final protective fire, shooting down crude ASMs. Don't want to have the Atomic Flak too close in, want to keep your fire control radar working so you can deal with wave #2, so for that you want conventional guns, and if the bugs get worked out the 3"/70 is the best for that

You would need more than that, you can't just have safe boxes because you need to prevent the engineering and other work spaces from being rendered radioactive so the crew can keep the ship running after the battle. Probably want detachable plates of radiation absorptive material outside essentially the entire hull that can be gotten rid of after the battle, and if you back the plates with an inch or two of STS they can also decap conventional AP shells

Yes the Komet would be vulnerable, really any non sea skimmer would be vulnerable to kiloton range atomic flak, but at this point the aircraft itself is no longer at risk and can just keep trying until they get lucky

 

[juanml82]

Wouldn't a nuclear SAM be effective against AShM? Have a helicopter equipped with a radar set to keep watch for sea skimming missiles. The helicopter detects the incoming missiles, the Atomic Dreadnought fires a nuclear SAM in their general direction, the blast tears apart the missiles.

Of course, even if that works, there is the problem of what happens to any allied ships and aircraft which may be caught by the blast and aren't radiation resistant.

 

[HMS Warspite]

Some data of targetlocations:
Test Able
https://en.wikipedia.org/wiki/File:Crossroads_Able_Target_Ship_Map.png
The array of target ships in Bikini lagoon for the Able shot of Operation Crossroads. Half of the target ships were outside the area of this map. The five red X's mark the five ships that sank. The tables (right) contain the key to ship numbers. The circle, with a radius of 1,000 yards (914 m) from the point of detonation, outlines the area of serious ship damage. The intended bullseye for the bomb was ship #32, the battleship USS Nevada, which was painted red to aid the bombardier. The bomb landed closer to ship #5, the attack transport USS Gilliam. All submarines were on the surface.

Location at which ships sank[64] # Name Type Yards from zero 5 Gilliam Transport 50 9 Sakawa Japanese cruiser 420 4 Carlisle Transport 430 1 Anderson Destroyer 600 6 Lamson Destroyer 760 Serious damage # Name Type Yards from zero 40 Skate Submarine 400 12 YO-160 Yard oiler 520 28 Independence Aircraft carrier 560 22 Crittenden Transport 595 32 Nevada Battleship 615 3 Arkansas Battleship 620 35 Pensacola Cruiser 710 11 ARDC-13 Drydock 825 23 Dawson Transport 855 38 Salt Lake City Cruiser 895 27 Hughes Destroyer 920 37 Rhind Destroyer 1,012 49 LST-52 LST 1,530 10 Saratoga Aircraft carrier 2,265

Test Baker

Ships sunk[64] # Name Type Yards from surface zero 50 LSM-60 Amphibious 0 3 Arkansas Battleship 170 8 Pilotfish Submarine 363 10 Saratoga Aircraft carrier 450 12 YO-160 Yard oiler 520 7 Nagato Battleship 770 41 Skipjack Submarine 800 2 Apogon Submarine 850 11 ARDC-13 Drydock 1,150

Arkansas[edit]

Arkansas was the closest ship to the bomb other than the ship from which it was suspended. The underwater shock wave crushed the starboard side of her hull, which faced the bomb, and rolled the battleship over onto her port side. It also ripped off the two starboard propellers and their shafts, along with the rudder and part of the stern, shortening the hull by 25 feet (7.6 m).[106]
At 562 feet (171 m) long, the battleship was three times as long as the water is deep. When the Wilson cloud lifted, the Arkansas was apparently bow-pinned to the sea floor with her truncated stern 350 feet (110 m) in the air.[86] Unable to sink straight down in the relatively shallow lagoon, she toppled backward into the water curtain of the spray column.[107]
She was next seen by Navy divers, the same year, lying upside down with her bow on the rim of the underwater bomb crater and stern angled toward the center. There was no sign of the superstructure or the big guns. The first diver to reach the Arkansas sank up to his armpits in radioactive mud. When National Park Service divers returned in 1989 and 1990, the bottom was again firm-packed sand, and the mud was gone. They were able to see the barrels of the forward guns, which had not been visible in 1946.[108]
All battleships are top heavy and tend to settle upside down when they sink. The Arkansas settled upside down, but a 1989 diver's sketch of the wreck shows hardly any of the starboard side of the hull, making it look like the ship is lying on her side. Most of the starboard side is present, but severely compacted.[107]
The superstructure has not been found. It was either stripped off and swept away or is lying under the hull, crushed and buried under sand which flowed back into the crater, partially refilling it. The only diver access to the inside is a tight squeeze through the port side casemate, called the "aircastle." The National Park Service divers practiced on the similar casemate of the battleship USS Texas, a museum ship, before entering the Arkansas in 1990.[109]


Battleship Arkansas upside down, 180 feet deep in Bikini Lagoon. Diver's sketch from a 1989 National Park Service dive.


Port casemate of the Arkansas in 1989, upside down against the bottom. The only diver's access into the ship, it was entered in 1946 and again in 1990.


A similar battleship, USS Texas, with casemate circled. At Bikini, everything that was above the lower deck guns of Arkansas is either missing or is buried in the sand.

 

[Simon Darkshade]

Getting offensive atomic battleships shells isn't a problem in the time frame, given the historical fielding of the W23 Katies.

It is far too early to get miniaturized shells for AA work; you might be able to get a 5" nuclear round by the mid-late 60s, when it was historically discussed.

The problems are myriad - the impact of shock on radar, electronics and equipment; attacking aircraft and missiles travelling too fast for conventional gun based defence and the irrelevance of armour against nuclear weapons. You might be able to keep the ship afloat after a near miss, but the crew are going to be in a bit of bother.

You might be better off going for a version of the BBG concept discussed in Friedman and Garzke and Dulin, keeping a forward turret or two and having Talos to the rear, Tartar on the beams and Regulus amidships. Even then it costs a lot and is a ship in search of a role.

The best option for an atomic dreadnoughty is something of a definitional cheat - build a large 25,000t nuclear powered missile-armed surface combatant and simply call it a battlecruiser or battleship, in the manner of the 1975 cruiser reclassification.

 

[RamscoopRaider]

Wouldn't a nuclear SAM be effective against AShM? Have a helicopter equipped with a radar set to keep watch for sea skimming missiles. The helicopter detects the incoming missiles, the Atomic Dreadnought fires a nuclear SAM in their general direction, the blast tears apart the missiles.

Of course, even if that works, there is the problem of what happens to any allied ships and aircraft which may be caught by the blast and aren't radiation resistant.

Muzzle Blast issues, SAM's are a bit sensitive to be within a hundred yards of the muzzle of a battleship gun

Getting offensive atomic battleships shells isn't a problem in the time frame, given the historical fielding of the W23 Katies.

It is far too early to get miniaturized shells for AA work; you might be able to get a 5" nuclear round by the mid-late 60s, when it was historically discussed.

Eh the 8"/55 Mark 16 was usable, albeit barely, in the AA role with conventional shells, and the W33 was available in 56, at 12 rounds a minute per barrel you could put a lot of fireballs in the way of inbound missiles

 

[Archibald]

Just put Gerald Bull in charge of overhauling the big guns. That guy was the great artillery genius of the 20th century.

 

[DrakonFin]

Wouldn't a nuclear SAM be effective against AShM? Have a helicopter equipped with a radar set to keep watch for sea skimming missiles. The helicopter detects the incoming missiles, the Atomic Dreadnought fires a nuclear SAM in their general direction, the blast tears apart the missiles.

Of course, even if that works, there is the problem of what happens to any allied ships and aircraft which may be caught by the blast and aren't radiation resistant.

I think that the ability to distract the incoming missiles would be more crucial as well as easier to achieve than trying to intercept them. IOTL the way to ward off such early ASMs as the Soviet P-15 Termit (SS-N-2 Styx) was to mess up its radar system with jamming or chaff, etc. This is what allowed the Israelis do so well against the Termits launched from the Osa and Komar class missile boats used by the Egyptians and Syrians in the Yom Kippur War. I'd assume the same principles would work with, say, the P-5/P-35 (SS-N-3 Shaddock) as well.

In fact the Shaddock is the kind of missile the designers of a Atomic Dreadnought probably should think about, given that it is one of the earliest Soviet ASMs with a nuclear warhead. See this page for a nice bit of info about Soviet cruise missiles.

 

[Vikingstar]

It depends on how close a detonation you need to be able to survive, and how optimized your armor is for resisting radiation. The gamma tenthing thickness for steel is about 3.3 inches, and a 10 kT device puts out 500 REM at a radius of 1.25 km, so 6.6 inches of steel - or 3.3 inches of steel and a bit more then an inch of lead - will cut that to 5 REM - not good for you, but not going to produce acute effects.

An 'atomic dreadnought" would be a bomb magnet; I think you could reliably count on multiple near misses, and lots and lots of rads.

 

[Simon Darkshade]

Eh the 8"/55 Mark 16 was usable, albeit barely, in the AA role with conventional shells, and the W33 was available in 56, at 12 rounds a minute per barrel you could put a lot of fireballs in the way of inbound missiles

Adapting an 8" round for naval purposes could be done, but it wouldn't be fired off in anywhere close to rapid fire. The procedure for firing the W23 was been outlined in Garzke and Dulin IIRC, consisting of a conventional ranging shot followed by a single nuclear round; there was some thinking of removing one gun from the triple turret to accomodate the atomic weapons.

Nuclear AA rounds are a non-starter for many practical reasons, as were 8" rounds employed in an AA role.

 

[HMS Warspite]

An 'atomic dreadnought" would be a bomb magnet; I think you could reliably count on multiple near misses, and lots and lots of rads.

Radiation is not so much the main problem on a warship, as these have anti radiation measures normally installed on them sicne the 50's The close proximity to the blast however is a problem, as the warhead is seriously capable of inflicting collosal damage by sheer force, rather than long term radiation. Luckily the Blastradius deteriorates the further it is form the source, so only a close proximity detonation will do damage, while a target a few miles away from the blast will escape unscatched normally.

 

[asnys]

You would need more than that, you can't just have safe boxes because you need to prevent the engineering and other work spaces from being rendered radioactive so the crew can keep the ship running after the battle. Probably want detachable plates of radiation absorptive material outside essentially the entire hull that can be gotten rid of after the battle, and if you back the plates with an inch or two of STS they can also decap conventional AP shells

Lingering radiation isn't a serious problem; you don't want to go on deck after a near-miss, but ordinary steel plate and a washdown system should be good enough under most circumstances to keep the rest of the ship livable. The dose rate is just a lot lower compared to the pulse generated by a detonation.

Of course, even if that works, there is the problem of what happens to any allied ships and aircraft which may be caught by the blast and aren't radiation resistant.

This is definitely not a ship that can play nice with any ship other then another atomic dreadnought.

Getting offensive atomic battleships shells isn't a problem in the time frame, given the historical fielding of the W23 Katies.

It is far too early to get miniaturized shells for AA work; you might be able to get a 5" nuclear round by the mid-late 60s, when it was historically discussed.

You might be able to get small-caliber nuclear shells earlier if the military pushes for them - historically, nuclear artillery was always a third-run priority for the weapons labs.

The best option for an atomic dreadnoughty is something of a definitional cheat - build a large 25,000t nuclear powered missile-armed surface combatant and simply call it a battlecruiser or battleship, in the manner of the 1975 cruiser reclassification.

But that's not nearly as cool.

Adapting an 8" round for naval purposes could be done, but it wouldn't be fired off in anywhere close to rapid fire. The procedure for firing the W23 was been outlined in Garzke and Dulin IIRC, consisting of a conventional ranging shot followed by a single nuclear round; there was some thinking of removing one gun from the triple turret to accomodate the atomic weapons.

Nuclear AA rounds are a non-starter for many practical reasons, as were 8" rounds employed in an AA role.

Why not? Sorry, I don't really know much of anything about artillery.

 

[Simon Darkshade]

1. The military might push for them, but some advances will take a fair bit of time and technology. What is needed is something smaller than the 155mm W48 round, which entered production in 1963. Even if that is knocked back 5-6 years, it is still well out of any battleship timing.

2. Reality is uncool and boring, but it works. I know where you are coming from, having looked at the issue myself about 14 years ago for some writing.

3. Conventional AA guns went out in the early 50s when jet aircraft simply went too fast for the gun mounts to move effectively. The threat had changed. The 8" automatic on the Des Moines class CAs had a very, very marginal AA role; the closest approximation would be some of the Japanese main armament AA barrages which were very ineffective. The probability of kill is very low.

If Eugene Slover's website is still around, there should be something on AA gunnery there.

Many navies dallied with 100-130mm rapid fire weapons in the late 1940s and early 1950s, but by the time they entered service, the threat had changed and was more capably countered by aircraft. As a result, we see the downrated Mk.42s in the USN and similar developments in RN 4.5" MCGs.

Nuclear artillery at sea was a shore bombardment weapon to support amphibious operations; I haven't read anything regarding its use as a defensive weapon.

 

[CalBear]

Short range nuclear AAA (or would that AAA-A for anti-aircraft artillery-atomic) is a non starter. The detonation flash would blind anyone looking in that direction without heavy goggles and dazzle those wearing them. The fallout and direct effects would also be terrifyingly lethal. As noted heavy gun nuclear rounds were actually produced so that is not an issue.

There isn't enough horsepower on Earth to power a BB with both sufficient standard armor plate to resist normal AP shells and torpedoes, and also provide sufficient shielding from extended exposure to near miss fallout. Short term there are ways to clean off the deposits, but in an extended time frame you run into issues.

There is also the definition of a near miss. As noted USS Arkansas was at Crossroads and was sunk. That doesn't really describe the event. She was moored 620 yards (roughly 1/3 of a mile or 0.6 kilometers) from the actual detonation point. Arkansas was 562 feet in length and displaced ~27,000 tons. The device yield was 23kT.

Arkansas is the black vertical object on the right side of the image.